This thoroughly revised and long awaited new edition of a classic text builds on the success of the 1991 third edition. Kuttruf considers the theory and practice of sound behavior in closed spaces; a key area for acoustical engineers worldwide. It is of particular interest to those working on auditoria and will therefore stand as an excellent complement to Barron's Auditorium Acoustics. This new edition includes important new material on the growth of digital technology and sound intensity.